EP0417705B1 - Method and system for aqueous sewage sludge disposal - Google Patents
Method and system for aqueous sewage sludge disposal Download PDFInfo
- Publication number
- EP0417705B1 EP0417705B1 EP90117411A EP90117411A EP0417705B1 EP 0417705 B1 EP0417705 B1 EP 0417705B1 EP 90117411 A EP90117411 A EP 90117411A EP 90117411 A EP90117411 A EP 90117411A EP 0417705 B1 EP0417705 B1 EP 0417705B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- gas
- cement
- quicklime
- solids
- sewage sludge
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000010801 sewage sludge Substances 0.000 title claims description 33
- 238000000034 method Methods 0.000 title claims description 29
- 239000004568 cement Substances 0.000 claims description 49
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 claims description 48
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 25
- 239000000292 calcium oxide Substances 0.000 claims description 24
- 235000012255 calcium oxide Nutrition 0.000 claims description 24
- 239000002994 raw material Substances 0.000 claims description 22
- 239000007787 solid Substances 0.000 claims description 22
- 239000000463 material Substances 0.000 claims description 18
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 14
- 239000010802 sludge Substances 0.000 claims description 9
- 230000018044 dehydration Effects 0.000 claims description 8
- 238000006297 dehydration reaction Methods 0.000 claims description 8
- 238000004821 distillation Methods 0.000 claims description 8
- 238000002156 mixing Methods 0.000 claims description 6
- 239000000126 substance Substances 0.000 claims description 6
- 229910021529 ammonia Inorganic materials 0.000 claims description 5
- 239000002893 slag Substances 0.000 claims description 4
- 238000006243 chemical reaction Methods 0.000 claims description 3
- 239000002245 particle Substances 0.000 claims description 3
- 239000010459 dolomite Substances 0.000 claims description 2
- 229910000514 dolomite Inorganic materials 0.000 claims description 2
- 238000001914 filtration Methods 0.000 claims 1
- 238000010438 heat treatment Methods 0.000 claims 1
- 239000000203 mixture Substances 0.000 claims 1
- 238000011144 upstream manufacturing Methods 0.000 claims 1
- 239000007789 gas Substances 0.000 description 12
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 6
- 239000000920 calcium hydroxide Substances 0.000 description 6
- 235000011116 calcium hydroxide Nutrition 0.000 description 6
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 6
- 239000000470 constituent Substances 0.000 description 5
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 4
- 241000196324 Embryophyta Species 0.000 description 4
- 235000011941 Tilia x europaea Nutrition 0.000 description 4
- 239000004571 lime Substances 0.000 description 4
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 3
- 235000011114 ammonium hydroxide Nutrition 0.000 description 3
- 239000002361 compost Substances 0.000 description 3
- 239000000428 dust Substances 0.000 description 3
- 239000000446 fuel Substances 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 235000019738 Limestone Nutrition 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 238000013019 agitation Methods 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000000855 fermentation Methods 0.000 description 2
- 230000004151 fermentation Effects 0.000 description 2
- 239000006028 limestone Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000006386 neutralization reaction Methods 0.000 description 2
- 229910000069 nitrogen hydride Inorganic materials 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 239000010865 sewage Substances 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- 206010067482 No adverse event Diseases 0.000 description 1
- 240000007594 Oryza sativa Species 0.000 description 1
- 235000007164 Oryza sativa Nutrition 0.000 description 1
- 239000011398 Portland cement Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 239000010842 industrial wastewater Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 235000009566 rice Nutrition 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2/00—Lime, magnesia or dolomite
- C04B2/02—Lime
- C04B2/04—Slaking
- C04B2/06—Slaking with addition of substances, e.g. hydrophobic agents ; Slaking in the presence of other compounds
- C04B2/066—Making use of the hydration reaction, e.g. the reaction heat for dehydrating gypsum; Chemical drying by using unslaked lime
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B7/00—Hydraulic cements
- C04B7/24—Cements from oil shales, residues or waste other than slag
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E50/00—Technologies for the production of fuel of non-fossil origin
- Y02E50/30—Fuel from waste, e.g. synthetic alcohol or diesel
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
- Y02P40/10—Production of cement, e.g. improving or optimising the production methods; Cement grinding
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
- Y02P40/40—Production or processing of lime, e.g. limestone regeneration of lime in pulp and sugar mills
- Y02P40/45—Production or processing of lime, e.g. limestone regeneration of lime in pulp and sugar mills using fuels from renewable energy sources
Definitions
- This invention relates to a system for disposal of aqueous sewage sludge by using it to make cement. Recently, amounts of sewage sludge released mainly from waste water treatment plants are increasing year by year, and are being treated by various processes.
- sewage sludge is mixed with fermentation auxiliaries, such as rice hulls and saw dust, and subjected to fermentation to produce compost.
- fermentation auxiliaries such as rice hulls and saw dust
- This compost is used for farmland, but its consumption is limited in quantity, and it is difficult to consume and reduce large amounts of compost.
- Another method is to throw untreated sewage sludge into the seas. But regulations are gradually becoming stricter and this method is not desirable in view of the need for protection of the environment. Another method is to spread the sludge on farmland expecting fertilizing effects, but it is difficult to dispose of large amounts by this method.
- Untreated sewage sludge is used in land reclamation, or sewage sludge is solidified with a solidification agent such as cement or lime and used in reclamation.
- a solidification agent such as cement or lime
- Sewage sludge has been burned in order to reduce the volume.
- this method releases large amounts of ash, which are usually disposed of by reclamation and hence the disposable amounts are limited. Part of the ash is used in architectural and horticultural materials, but amounts of consumption in these areas are also limited. Furthermore, this method has the inherent problem of high combustion costs.
- a system for utilizing sewage sludge comprising a combination of a dehydration process for dehydrating the sewage sludge by mixing a quicklime-containing material, a cement conversion process for putting solids released from the dehydration process in a cement kiln with other cement raw materials to yield cement, and a gas treatment process for introducing gases released from the dehydration process into a cement burning process.
- Fig.1 is a diagram showing a cement burning process in an embodiment of the present invention.
- Sewage sludge in the present invention means sludge released mainly from sewage treatment plants, and includes sludges released from treatment of raw sewage, home waste water, and industrial waste water. Water contents of these sludges are normally 60% or more.
- the quicklime-containing material to be mixed with sewage sludge in the present invention comprises CaO which reacts with the water in the sewage sludge to produce slaked lime.
- the quicklime-containing material includes quicklime, calcined dolomite, granulated slag, and blast furnace slag and contains at least 30% CaO, preferably at least 70%; other constituents may also be present if they do not interfere with the production of cement.
- the quicklime-containing material has a particle diameter of 70 mm or less, preferably 30 mm or less.
- the ratio of sewage sludge to the quicklime-containing material is not specifically limited, however, since it is necessary to dehydrate the sewage sludge by mixing to produce solids which can be converted into cement in the subsequent process, the ratio of quicklime-containing material/sewage sludge is typically 1.5 to 0.5, preferably 1 to 0.7.
- Mixing is accomplished by mechanical agitation using a paddle mixer, pug mill, or the like, at a rotational speed of 10 to 80 rpm, preferably 20 to 50 rpm, and for a mixing time of 1 to 30 minutes, preferably 3 to 20 minutes.
- the solids, containing 20% or less of water, produced by the dehydration process comprise slaked lime and the solid constituents of the sewage sludge.
- the solids produced by the dehydration process are then converted into cement.
- the solids are put into a cement raw material handling system such as a dryer or a mill at a cement plant. Then, in the cement kiln, the slaked lime and inorganic substances in the solid constituents of the sludge become the raw materials of the cement, and organic substances in the solid constituents of the sludge become fuel for cement burning.
- the dehydration process releases malodorous gases such as ammonia (NH3) which are treated by introducing them into the cement burning process.
- gases are generated together with dust, which is mainly slaked lime fine powder, and water vapor which has adverse effects on cement burning in a dry process. Therefore, it is desirable that such fine powder be removed as by a bag filter or the like and water vapor be removed as by a distillation column or the like. Thereafter, the result is introduced by way of a rear port of the cement kiln, into the cement burning process. This decomposes the malodorous gases and, in particular, denitration occurs due to the ammonia. Water vapor is collected as drain water from the distillation column. When the drain water is dilute ammonia water, it is neutralized and then discharged.
- NH3 ammonia
- the present invention can treat sewage sludge entirely in the cement plant and does not release any wastes. Furthermore, organic substances in the sludge can be utilized as a fuel, thereby supplying heat for cement burning and reducing the NO x content of the cement kiln exhaust gas.
- Cement types that can be produced by cement burning to which the present invention is applied are not specifically limited and include Portland cement and alumina cement.
- the amount of the sludge solid constituents is 30 weight % or less based on the total amount of the cement raw materials, the sludge can be treated with no adverse effects on the properties of the resulting cement.
- Fig.1 shows a cement burning process in a cement plant to which the present invention is applied.
- lime raw material stored in a stockyard 1A and silica, alumina, and iron-based raw materials stored in a stockyard 1B are respectively introduced into raw material crusher 4 through dryers 2A and 2B and feeders 3A and 3B.
- raw material crusher 4 introduced into raw material silo 5, preheated by raw material preheater 6, and then fired in cement burning kiln 7 into cement clinkers.
- the above procedure is the same as that in ordinary cement production plants.
- Sewage sludge and a quicklime-based material are respectively introduced from hoppers 8 and 9 into mixer 10, which is a paddle mixer.
- the sewage sludge and quicklime-based material are reacted in mixer 10 at an agitation speed of 30 rpm, and the resulting solids are transferred by ager/carrier 11 to raw material crusher 4.
- Water vapor generated from mixer 10 is passed through bag filter 12 to collect dust such as slaked lime, and the remaining water vapor is introduced into distillation column 13. Water vapor is removed by distillation column 13, and remaining gases, which mainly comprise ammonia, are introduced into calcining furnace 6a. Dilute ammonia water released from distillation column 13 is neutralized in neutralization tank 14 and discharged as clean water.
- This cement plant operates 24 hours a day using 3,000 tons/day (lime-containing raw materials are approximately 80% of the input) to produce 2,000 tons/day of cement.
- Sewage sludge containing 78% water from hopper 8 and quicklime of 30 mm or less in particle size from hopper 9 were introduced at rates of 5 tons/hour (120 tons/day) and 5 tons/hour (120 tons/day), respectively, into mixer 10.
- Solids produced by mixer 10 were charged into raw material crusher 4 through ager/carrier 11. During this operation, the amount of limestone in the cement raw materials was reduced by 9 tons per hour. Furthermore, heat of 2.75 million Kcal per hour was produced from organic substances contained in the solid components of the sewage sludge.
- solids obtained in the dehydration process are fed to raw material crusher 4 in the above-described Examples, but these may be introduced into the lime-containing raw material in stockyard 1A or dryer 2A.
- the present invention converts sewage sludge into cement without releasing wastes, and reduces the amount of fuel needed for cement burning and the NO x content of the exhaust gas.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Treatment Of Sludge (AREA)
- Processing Of Solid Wastes (AREA)
Description
- This invention relates to a system for disposal of aqueous sewage sludge by using it to make cement. Recently, amounts of sewage sludge released mainly from waste water treatment plants are increasing year by year, and are being treated by various processes.
- For example, sewage sludge is mixed with fermentation auxiliaries, such as rice hulls and saw dust, and subjected to fermentation to produce compost. This compost is used for farmland, but its consumption is limited in quantity, and it is difficult to consume and reduce large amounts of compost.
- Another method is to throw untreated sewage sludge into the seas. But regulations are gradually becoming stricter and this method is not desirable in view of the need for protection of the environment. Another method is to spread the sludge on farmland expecting fertilizing effects, but it is difficult to dispose of large amounts by this method.
- Untreated sewage sludge is used in land reclamation, or sewage sludge is solidified with a solidification agent such as cement or lime and used in reclamation. However, it is becoming difficult year by year to find lands to be reclaimed; thus limiting the disposable amounts.
- Sewage sludge has been burned in order to reduce the volume. However, this method releases large amounts of ash, which are usually disposed of by reclamation and hence the disposable amounts are limited. Part of the ash is used in architectural and horticultural materials, but amounts of consumption in these areas are also limited. Furthermore, this method has the inherent problem of high combustion costs.
- With a view to these prior art problems, it is a primary object of the present invention to provide a system for utilizing sewage sludge in a manner which can efficiently treat large amounts thereof.
- In accordance with the present invention which attains the above object, there is provided a system for utilizing sewage sludge comprising a combination of a dehydration process for dehydrating the sewage sludge by mixing a quicklime-containing material, a cement conversion process for putting solids released from the dehydration process in a cement kiln with other cement raw materials to yield cement, and a gas treatment process for introducing gases released from the dehydration process into a cement burning process.
- Fig.1 is a diagram showing a cement burning process in an embodiment of the present invention.
- Sewage sludge in the present invention means sludge released mainly from sewage treatment plants, and includes sludges released from treatment of raw sewage, home waste water, and industrial waste water. Water contents of these sludges are normally 60% or more.
- The quicklime-containing material to be mixed with sewage sludge in the present invention comprises CaO which reacts with the water in the sewage sludge to produce slaked lime. Specifically, the quicklime-containing material includes quicklime, calcined dolomite, granulated slag, and blast furnace slag and contains at least 30% CaO, preferably at least 70%; other constituents may also be present if they do not interfere with the production of cement. The quicklime-containing material has a particle diameter of 70 mm or less, preferably 30 mm or less.
- In the present invention, the ratio of sewage sludge to the quicklime-containing material is not specifically limited, however, since it is necessary to dehydrate the sewage sludge by mixing to produce solids which can be converted into cement in the subsequent process, the ratio of quicklime-containing material/sewage sludge is typically 1.5 to 0.5, preferably 1 to 0.7. Mixing is accomplished by mechanical agitation using a paddle mixer, pug mill, or the like, at a rotational speed of 10 to 80 rpm, preferably 20 to 50 rpm, and for a mixing time of 1 to 30 minutes, preferably 3 to 20 minutes.
- When sewage sludge is mixed with the quicklime-containing material, water in the sewage sludge reacts therewith to yield slaked lime. Therefore, the solids, containing 20% or less of water, produced by the dehydration process comprise slaked lime and the solid constituents of the sewage sludge.
- In the present invention, the solids produced by the dehydration process are then converted into cement. Specifically, the solids are put into a cement raw material handling system such as a dryer or a mill at a cement plant. Then, in the cement kiln, the slaked lime and inorganic substances in the solid constituents of the sludge become the raw materials of the cement, and organic substances in the solid constituents of the sludge become fuel for cement burning.
- However, the dehydration process releases malodorous gases such as ammonia (NH₃) which are treated by introducing them into the cement burning process. These gases are generated together with dust, which is mainly slaked lime fine powder, and water vapor which has adverse effects on cement burning in a dry process. Therefore, it is desirable that such fine powder be removed as by a bag filter or the like and water vapor be removed as by a distillation column or the like. Thereafter, the result is introduced by way of a rear port of the cement kiln, into the cement burning process. This decomposes the malodorous gases and, in particular, denitration occurs due to the ammonia. Water vapor is collected as drain water from the distillation column. When the drain water is dilute ammonia water, it is neutralized and then discharged.
- As described above, the present invention can treat sewage sludge entirely in the cement plant and does not release any wastes. Furthermore, organic substances in the sludge can be utilized as a fuel, thereby supplying heat for cement burning and reducing the NOx content of the cement kiln exhaust gas.
- Cement types that can be produced by cement burning to which the present invention is applied are not specifically limited and include Portland cement and alumina cement. When the amount of the sludge solid constituents is 30 weight % or less based on the total amount of the cement raw materials, the sludge can be treated with no adverse effects on the properties of the resulting cement.
- The present invention will now be described with reference to the embodiments.
- Fig.1 shows a cement burning process in a cement plant to which the present invention is applied. Referring to Fig.1, lime raw material stored in a
stockyard 1A and silica, alumina, and iron-based raw materials stored in astockyard 1B are respectively introduced into raw material crusher 4 throughdryers feeders raw material silo 5, preheated by raw material preheater 6, and then fired incement burning kiln 7 into cement clinkers. The above procedure is the same as that in ordinary cement production plants. - Sewage sludge and a quicklime-based material are respectively introduced from
hoppers mixer 10, which is a paddle mixer. The sewage sludge and quicklime-based material are reacted inmixer 10 at an agitation speed of 30 rpm, and the resulting solids are transferred by ager/carrier 11 to raw material crusher 4. Water vapor generated frommixer 10 is passed throughbag filter 12 to collect dust such as slaked lime, and the remaining water vapor is introduced intodistillation column 13. Water vapor is removed bydistillation column 13, and remaining gases, which mainly comprise ammonia, are introduced into calciningfurnace 6a. Dilute ammonia water released fromdistillation column 13 is neutralized inneutralization tank 14 and discharged as clean water. - Using the above-described procedure, the following experimental operations were carried out. This cement plant operates 24 hours a day using 3,000 tons/day (lime-containing raw materials are approximately 80% of the input) to produce 2,000 tons/day of cement.
- Sewage sludge containing 78% water from
hopper 8 and quicklime of 30 mm or less in particle size fromhopper 9 were introduced at rates of 5 tons/hour (120 tons/day) and 5 tons/hour (120 tons/day), respectively, intomixer 10. Solids produced bymixer 10 were charged into raw material crusher 4 through ager/carrier 11. During this operation, the amount of limestone in the cement raw materials was reduced by 9 tons per hour. Furthermore, heat of 2.75 million Kcal per hour was produced from organic substances contained in the solid components of the sewage sludge. - 20,000 ppm of NH₃ gas was detected in the water vapor released from
mixer 10. This water vapor was passed throughbag filter 12 todistillation column 13, and the resulting gases (mainly comprising ammonia) were fed tocement burning kiln 7 through its rear port. As a result, the NOx content of the exhaust gas was decreased from an average of 400 ppm to an average of 300 ppm, thereby facilitating NOx reduction treatment.Distillation column 13 released 0.04% dilute ammonia water, which was diluted with sulfuric acid in theneutralization tank 14 and then discharged. - A similar operation was carried out with sewage sludge containing 78% water at a feed rate of 10 tons/hour, quicklime at a feed rate of 10 tons/hour, and a decrease in limestone amount of 18 tons/hour in the cement raw materials. As a result, heat of 5.5 million Kcal was produced from organic substances contained in the solid components of the sewage sludge. Furthermore, the NOx content of the exhaust gas was reduced from an average of 400 ppm to an average of 200 ppm.
- Cement produced in accordance with Examples 1 and 2 had the same properties as ordinary cement.
- Needless to say, solids obtained in the dehydration process are fed to raw material crusher 4 in the above-described Examples, but these may be introduced into the lime-containing raw material in
stockyard 1A ordryer 2A. - As described above, the present invention converts sewage sludge into cement without releasing wastes, and reduces the amount of fuel needed for cement burning and the NOx content of the exhaust gas.
Claims (12)
- A method for the disposal of aqueous sewage sludge comprising:- dehydrating said sludge by mixing with a quicklime-containing material to form solids and a gas, said gas containing ammonia and water vapor,- converting said solids to cement by a process of heating with other cement-forming materials, wherein said solids are present in a maximum amount of 30 % by weight based on the total weight of the cement raw materials, and- separating said gas from said water vapor and introducing said gas into said process.
- The method of Claim 1, wherein said gas is mixed with quicklime fines, comprising filtering said gas to remove said fines, and distilling said gas and water vapor to remove said water vapor.
- A system for the disposal of aqueous sewage sludge comprising:- a dehydration means (8 to 12) for dehydrating said sewage sludge by mixing said sludge with a quicklime-containing material to form solids and a gas, said gas being mixed with water vapor,- a cement conversion means (1a to 7) comprising a cement burning means (7) for converting said solids in a kiln (7) with other cement raw materials, wherein said solids are added to said kiln (7) in a maximum amount of 30 % by weight based on the total weight of cement raw materials, and- a treatment means (13) for separating said gas from said water vapor and introducing said gas into said conversion means (1a to 7) at or upstream (6a) of said burning means (7).
- The system of Claim 3, wherein said quicklime-containing material is selected from the group consisting of quicklime, calcined dolomite, granulated slag, blast furnace slag, and mixtures thereof.
- The system of any one of Claims 3 or 4, wherein the ratio of said quicklime-containing material/sewage sludge is 1.5 to 0.5.
- The system of any of the Claims 3 to 5, wherein said quicklime-containing material contains at least 30 % by weight of CaO.
- The system of any one of the Claims 3 to 6, wherein said quicklime-containing material has a particle diameter not exceeding 70 mm, preferably not exceeding 30 mm.
- The system of any one of the Claims 3 to 7, wherein said sewage sludge is mixed with said quicklime-containing material by a paddle mixer (10) or a pug mill (10).
- The system of any one of Claims 3 to 8, wherein said solids are added to said kiln (7) by way of its raw material system (4, 5, 6).
- The system of any one of Claims 3 to 9, wherein said solids contain a maximum of 20 % by weight of water.
- The system of any one of Claims 3 to 10, wherein said gas is filtered by a bag filter (12) or the like to remove particulate substances, and water vapor is removed by a distillation column (13) or the like.
- The system of any one of Claims 3 to 11, wherein said gas is introduced into said cement burning means (7) at a rear port of said kiln (7).
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP232733/89 | 1989-09-11 | ||
JP1232733A JP2803855B2 (en) | 1989-09-11 | 1989-09-11 | Sewage sludge recycling system |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0417705A1 EP0417705A1 (en) | 1991-03-20 |
EP0417705B1 true EP0417705B1 (en) | 1995-05-24 |
Family
ID=16943928
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP90117411A Expired - Lifetime EP0417705B1 (en) | 1989-09-11 | 1990-09-10 | Method and system for aqueous sewage sludge disposal |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP0417705B1 (en) |
JP (1) | JP2803855B2 (en) |
DE (1) | DE69019643T2 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN110577349A (en) * | 2019-10-23 | 2019-12-17 | 深圳研源环境科技有限公司 | Building slurry treatment process and application |
Families Citing this family (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB9217594D0 (en) * | 1992-08-19 | 1992-09-30 | Reads Plc | Process for the treatment of sludge |
WO1995025075A1 (en) * | 1994-03-16 | 1995-09-21 | Cement Industry Environmental Consortium | Method and system for controlling pollutant emissions in combustion operations |
JP4629170B2 (en) * | 1999-03-25 | 2011-02-09 | 太平洋セメント株式会社 | Portland cement clinker and Portland cement |
JP4110749B2 (en) * | 2001-05-29 | 2008-07-02 | 三菱マテリアル株式会社 | Treatment method of sludge and combustible waste |
SE521573C2 (en) * | 2001-05-30 | 2003-11-11 | Roland Lundqvist | Method and apparatus for extinguishing lime raw material or other extinguishable material |
KR100554009B1 (en) * | 2004-07-01 | 2006-02-22 | 주식회사 젝시엔 | Method and apparatus for removing organic sludge |
JP4775045B2 (en) * | 2006-03-14 | 2011-09-21 | 宇部興産株式会社 | Reducing gypsum composition, method for producing the same, cement-based solidifying material, and solidifying method |
JP5854507B2 (en) * | 2012-02-27 | 2016-02-09 | 太平洋セメント株式会社 | Biomass waste utilization method and cement raw fuel conversion device |
CN102923923A (en) * | 2012-10-12 | 2013-02-13 | 北京水泥厂有限责任公司 | Method for reducing nitric oxides by using disposed sludge |
CN103626380B (en) * | 2013-11-20 | 2014-11-05 | 同济大学 | Method for further dehydration of lime-dried urban domestic sewage sludge in cement kiln before treatment |
JP2017205682A (en) * | 2016-05-16 | 2017-11-24 | 株式会社トクヤマ | Manufacturing method of improved body of construction generated soil and/or sludge, and manufacturing method of cement clinker using the improved body |
CN107459305A (en) * | 2017-08-04 | 2017-12-12 | 福建港湾岩土工程集团有限公司 | A kind of curing agent that municipal sludge is processed into haydite |
RU2756513C1 (en) | 2018-01-18 | 2021-10-01 | Кавасаки Дзюкогио Кабусики Кайся | Method for processing sludge and cement production system |
CN110557945A (en) | 2018-04-04 | 2019-12-10 | 太平洋工程株式会社 | Organic sludge treatment device and treatment method |
JP7143233B2 (en) * | 2019-02-05 | 2022-09-28 | 太平洋セメント株式会社 | Incineration ash disposal method |
CN112876184A (en) * | 2021-02-01 | 2021-06-01 | 重庆大学 | Sludge curing agent and preparation method and use method thereof |
WO2023188114A1 (en) * | 2022-03-30 | 2023-10-05 | 太平洋セメント株式会社 | Apparatus and method for treating organic sludge |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3542145A1 (en) * | 1985-11-28 | 1987-06-04 | Krupp Polysius Ag | Process for the manufacture of cement |
DE3545317A1 (en) * | 1985-12-20 | 1987-06-25 | Kloeckner Humboldt Deutz Ag | Process and system for denitrogenating exhaust gases |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2537020A1 (en) * | 1974-08-21 | 1976-03-04 | Coopers Swindon Ltd | TREATMENT OF SEWAGE SLUDGE |
DE2917123A1 (en) * | 1978-04-28 | 1979-11-08 | Nihon Automatic Machinery Mfg | METHOD AND DEVICE FOR TREATMENT OF POLLUTED WATER |
IT1164202B (en) * | 1983-04-29 | 1987-04-08 | Ecodeco Sist Srl | PROCESS FOR THE PRODUCTION OF CEMENTITIOUS MATERIAL STARTING FROM INDUSTRIAL AND URBAN WORKING SLUDGE |
EP0141932A3 (en) * | 1983-08-25 | 1986-11-26 | Klöckner-Humboldt-Deutz Aktiengesellschaft | Method and apparatus for the pollutant-free disposal of noxious and waste materials with a low calorific value, esp. refuse, by burning |
EP0162215B1 (en) * | 1984-03-27 | 1989-08-09 | Alexander Grisar | Process for the disposal of combustible refuses |
DE3542004A1 (en) * | 1985-11-28 | 1987-06-04 | Kloeckner Humboldt Deutz Ag | Drying and combustion of sludges in the firing of mineral materials |
-
1989
- 1989-09-11 JP JP1232733A patent/JP2803855B2/en not_active Expired - Fee Related
-
1990
- 1990-09-10 DE DE69019643T patent/DE69019643T2/en not_active Expired - Fee Related
- 1990-09-10 EP EP90117411A patent/EP0417705B1/en not_active Expired - Lifetime
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3542145A1 (en) * | 1985-11-28 | 1987-06-04 | Krupp Polysius Ag | Process for the manufacture of cement |
DE3545317A1 (en) * | 1985-12-20 | 1987-06-25 | Kloeckner Humboldt Deutz Ag | Process and system for denitrogenating exhaust gases |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN110577349A (en) * | 2019-10-23 | 2019-12-17 | 深圳研源环境科技有限公司 | Building slurry treatment process and application |
Also Published As
Publication number | Publication date |
---|---|
JPH0398700A (en) | 1991-04-24 |
DE69019643D1 (en) | 1995-06-29 |
DE69019643T2 (en) | 1995-11-30 |
EP0417705A1 (en) | 1991-03-20 |
JP2803855B2 (en) | 1998-09-24 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US5217624A (en) | Method for the disposal of aqueous sewage sludge | |
EP0417705B1 (en) | Method and system for aqueous sewage sludge disposal | |
US5435923A (en) | Method for the treatment of sewage sludge and the like | |
KR101925418B1 (en) | Method for producing phosphate fertilizer | |
US5199987A (en) | Method of producing cement clinker | |
US20050066860A1 (en) | Use of organic waste/mineral by-product mixtures in cement manufacturing processes | |
EP0889859A1 (en) | Sludge handling and feeding system | |
JP3684410B2 (en) | Sewage sludge treatment method and treated sewage sludge | |
CN116371875A (en) | System and method for treating waste incineration fly ash | |
JP4040035B2 (en) | Sewage sludge treatment method and apparatus | |
EP0124038A2 (en) | Process for producing cement material from industrial processing and urban slurries | |
JPH1135358A (en) | Production of artificial lightweight aggregate | |
JP3356859B2 (en) | Sludge treatment method | |
JP3682669B2 (en) | Treatment method of organic sludge | |
JP4387040B2 (en) | Soil improver and / or organic fertilizer and method for producing the same | |
SK101093A3 (en) | Granulated fuel from slurry and process for producing it | |
KR100256021B1 (en) | Method of treating sewage sludge | |
JP7143233B2 (en) | Incineration ash disposal method | |
JPH09323099A (en) | Treatment of sludge | |
JPS6082192A (en) | Treatment of organic sludge | |
KR100467851B1 (en) | Treatment of Organic Sludge | |
JPH0650505A (en) | Desulfurizing agent used both for fuel and manufacture thereof | |
CN109437616B (en) | Method and system for preparing cement by using municipal sludge | |
DE10061014A1 (en) | Processing organic waste, especially from animal carcass disposal plants, to give fertilizer or soil additive, by mixing successively with calcium oxide, water or sludge and further calcium oxide | |
JP2001261477A (en) | Method for manufacturing organic fertilizer and/or soil conditioner |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): CH DE GB LI |
|
17P | Request for examination filed |
Effective date: 19910524 |
|
17Q | First examination report despatched |
Effective date: 19920902 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): CH DE GB LI |
|
REF | Corresponds to: |
Ref document number: 69019643 Country of ref document: DE Date of ref document: 19950629 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 19950830 Year of fee payment: 6 |
|
RIN2 | Information on inventor provided after grant (corrected) |
Free format text: YAMANE, ISAO, C/O ONODA CEMENT CO., LTD. * SAITO, TORU, C/O ONODA CEMENT CO., LTD. * SHIMODA, MASAO, C/O ONODA CHEMICO CO.,LTD. * KOUCHI, SATOSHI, C/O ONODA CHEMICO CO., LTD. |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 19951127 Year of fee payment: 6 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: CH Payment date: 19951201 Year of fee payment: 6 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Effective date: 19960910 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LI Effective date: 19960930 Ref country code: CH Effective date: 19960930 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 19960910 |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Effective date: 19970603 |